Question: Simplify the following expression: $k = \dfrac{2t^2 + t}{6rt - 3t} - \dfrac{3st + 2t}{6rt - 3t}$ You can assume $r,s,t \neq 0$.
Solution: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{2t^2 + t - (3st + 2t)}{6rt - 3t}$ $k = \dfrac{2t^2 - t - 3st}{6rt - 3t}$ The numerator and denominator have a common factor of $t$, so we can simplify $k = \dfrac{2t - 1 - 3s}{6r - 3}$